Come on now, let's put the energy in getting an answer from the manufacturers.
I have written them an email to sales and jerry. Anyone who can call them? They did a test period on their prototype pulley, did this sound not occur on their prototype? There are approx 30 EC sc pulleys sold I would have guessed, how many got issues of this sound? Is it due the alignment,gap is uneven and not 100% straight?

180, u got connections at EC?